EP0573039B1 - Fibre mats containing a binding agent made from cellulosic and ligno-cellulosic fibres - Google Patents

Fibre mats containing a binding agent made from cellulosic and ligno-cellulosic fibres Download PDF

Info

Publication number
EP0573039B1
EP0573039B1 EP93108937A EP93108937A EP0573039B1 EP 0573039 B1 EP0573039 B1 EP 0573039B1 EP 93108937 A EP93108937 A EP 93108937A EP 93108937 A EP93108937 A EP 93108937A EP 0573039 B1 EP0573039 B1 EP 0573039B1
Authority
EP
European Patent Office
Prior art keywords
outer layers
mat
fiber
mats
layer
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Expired - Lifetime
Application number
EP93108937A
Other languages
German (de)
French (fr)
Other versions
EP0573039A1 (en
Inventor
Albert Dr. Nicolay
Klaus Melzer
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Lignotock GmbH
Original Assignee
Lignotock GmbH
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Lignotock GmbH filed Critical Lignotock GmbH
Publication of EP0573039A1 publication Critical patent/EP0573039A1/en
Application granted granted Critical
Publication of EP0573039B1 publication Critical patent/EP0573039B1/en
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

Links

Images

Classifications

    • BPERFORMING OPERATIONS; TRANSPORTING
    • B27WORKING OR PRESERVING WOOD OR SIMILAR MATERIAL; NAILING OR STAPLING MACHINES IN GENERAL
    • B27NMANUFACTURE BY DRY PROCESSES OF ARTICLES, WITH OR WITHOUT ORGANIC BINDING AGENTS, MADE FROM PARTICLES OR FIBRES CONSISTING OF WOOD OR OTHER LIGNOCELLULOSIC OR LIKE ORGANIC MATERIAL
    • B27N3/00Manufacture of substantially flat articles, e.g. boards, from particles or fibres
    • B27N3/08Moulding or pressing
    • B27N3/10Moulding of mats
    • B27N3/14Distributing or orienting the particles or fibres
    • B27N3/143Orienting the particles or fibres

Definitions

  • Binder-containing fiber mats made of cellulose or lignocellulosic fibers (wood fibers), which are processed into molded parts by hot pressing, are known in a wide variety of compositions and are pressed into self-supporting molded parts in various ways.
  • the shaping possibilities of such fiber mats during hot pressing are primarily limited by their inadequate tensile strength.
  • the low fiber cohesion of the only moderately compacted mats very soon leads to fiber separations during the forming process, so that locally faulty molded parts as rejects cannot always be avoided.
  • Binder concentrations in the surface influence the physical characteristics of the finished molded part, but have no influence on the deformability of the fiber mats.
  • Deformation aids in the form of power transmission cloths between the tool and the fiber mat stabilizing cloths
  • fabrics in the middle of the mat only leads to incomplete solutions to the problem.
  • the present problem can be characterized as follows: If complicated molded parts are desired, steaming of the wood fiber mats, multi-stage deformation and the use of stabilizing cloths are still necessary in production practice - all in all, an effort that makes production more difficult and more expensive.
  • the invention is therefore based on the object to provide wood fiber mats of the type described, the shaping behavior of which is improved without additional material expenditure.
  • outer layers defining the surfaces have a higher compression than the inner layers, which consist predominantly of the same material, initially increases their tensile strength, without additional material expenditure. They can therefore transmit more tensile forces and act like the additional stabilizing layers of the stated prior art.
  • Another advantage of mats according to the invention is that with an additional compression of more than 40% of the outer layers which contain at least 20% by weight of fiber material of the mat, the overall thickness of the mat is reduced.
  • Fiber mats of the type described are not only shaped in the manufacture of molded parts, but also compressed. Here occur at places where the molding surfaces of the tools are oriented approximately parallel to the pressing direction are shear forces in the fiber mat, which lead to tears and defects in the molded part.
  • the reduction in thickness of wood fiber mats according to the invention also creates better deformation conditions. In the central region of the mat, the fiber displaceability required for the deformability of the fiber mat is retained due to the lower mat compression given here.
  • the higher tensile strength of the higher density outer layers and the resulting improved deformability of the wood fiber mats, the still good mobility of the fibers in the larger part of the mat and the improved deformation conditions due to the improved geometrical conditions due to the reduced mat thickness work together in such a way that at Forming the mat blanks into shaped parts, the damping of the fiber mat blanks and additional traction-transmitting aids - such as fabric coverings - can be dispensed with in the majority of cases.
  • Wood fiber mats of the type described are in principle produced by spreading the glued wood fibers onto a running belt.
  • the fibers are given a preferred direction of orientation in the running direction of the belt.
  • the tensile strength of the outer layers with the higher compression is consequently anisotropic: across the direction of formation of the mats, it is significantly lower than in the direction of formation. This is disadvantageous for the formation of the mats into the molded part, since the tensile forces can act in any surface direction of the mat and must be transmitted.
  • the higher-density outer layer consists of a large number of individual layers, the fiber arrangements of which are approximately orthotropic to one another are oriented, that is to say they intersect approximately at an angle of 90 °, this disadvantage is avoided and the deformation properties of the fiber mat are independent of the directions of deformation, that is to say of the (later) molded part geometry.
  • the large number of individual layers from which the higher-density outer layers are formed with orthotropically oriented fibers makes it easier for the mats to be completely oriented in the entire volume of the outer layers, since only thin individual layers have to be "completely oriented".
  • a fiber orientation in which the orthotropic orientation of the fibers changes alternately in the individual layers can therefore be advantageous for mat production.
  • Wood fiber mats are often used to a small extent other fiber materials, e.g. Polymer fibers, mixed.
  • the term "longer fiber” refers to the length of the shorter wood fibers, which does not exceed 10 mm.
  • mats the outer layers of which have a specific weight of more than 0.5 g / cm 3, while the specific weight of the middle layer is between 0.3 and 0.4 g / cm 3, have an optimal range of properties with regard to manufacture and handling the mats as well as the molding production. Also the handling of the mats Their storage, for cutting and transportation is facilitated by higher density outer layers due to the increased plate rigidity.
  • Fig. 2 different scattering devices 6 are indicated for the formation of the outer layers, the thickened middle layer is spread by a further spreading head 7.
  • the circumferential belts 5, onto which the preferably identical and pre-glued fiber material is scattered, run in the direction of the arrow and effect the mat transport.
  • Two pairs of calender rolls 3 are preheated and cause both the compression of the two outer layers 2 and, if necessary, their stabilizing stabilization by softening at least one component of the binder without crosslinking.
  • a fiber orientation in the pre-compressed outer layers 2 of the fiber mat 1, 2 can be achieved, for example, in that the calender rolls 3 have surface patterns, for example in the form of oblique grooves.
  • FIG. 2 shows, for example, how three-layer mats 8 according to the invention can be produced. Other procedures, even a larger number of layers are possible; e.g. outer layers 2 identical to the material can also be prefabricated separately and connected to the middle layer 1 in another way.

Landscapes

  • Life Sciences & Earth Sciences (AREA)
  • Engineering & Computer Science (AREA)
  • Manufacturing & Machinery (AREA)
  • Wood Science & Technology (AREA)
  • Forests & Forestry (AREA)
  • Dry Formation Of Fiberboard And The Like (AREA)
  • Nonwoven Fabrics (AREA)
  • Laminated Bodies (AREA)

Description

Bindemittelhaltige Fasermatten aus Zellulose- bzw. Lignozellulosefasern (Holzfasern), die durch Heißpressen zu Formteilen verarbeitet werden, sind in mannigfaltiger Zusammensetzung bekannt und werden auf verschiedenste Weise zu selbsttragenden Formteilen verpreßt. Die Formgebungsmöglichkeiten derartiger Fasermatten bei warmem Verpressen werden dabei vor allem durch deren mangelhafte Zugfestigkeit begrenzt. Der geringe Faserzusammenhalt der nur mittelstark verdichteten Matten führt sehr bald zu Fasertrennungen während des Umformvorganges, so daß ortlich fehlerhaftge Formteile als Ausschußware nciht immer zu vermeiden sind.Binder-containing fiber mats made of cellulose or lignocellulosic fibers (wood fibers), which are processed into molded parts by hot pressing, are known in a wide variety of compositions and are pressed into self-supporting molded parts in various ways. The shaping possibilities of such fiber mats during hot pressing are primarily limited by their inadequate tensile strength. The low fiber cohesion of the only moderately compacted mats very soon leads to fiber separations during the forming process, so that locally faulty molded parts as rejects cannot always be avoided.

In der Vergangenheit gab es daher mancherlei technologischen Anregungen, um das Umformverhalten - wenn möglich, gekoppelt an eine Formteilverbesserung - zu verbessern. In nahezu allen Fällen wird eine derartige Verbesserung durch die Anwendung der sogenannten Faserverbund-Technologie angestrebt, wobei die Holzfasern in recht unterschiedlicher Weise mit Kunst- oder Naturfasern kombiniert bzw. verbunden werden.In the past, there were therefore various technological suggestions to improve the forming behavior - if possible, coupled with an improvement of the molded part improve. In almost all cases, such an improvement is sought through the use of the so-called fiber composite technology, with the wood fibers being combined or connected with synthetic or natural fibers in quite different ways.

Im einzelnen läßt sich die technologische Entwicklung gemäß dem hier interessierenden Stand anhand der nachfolgend aufgeführten Stichworte klassifizieren:

  • Anreichung der Mattenoberflächen mit zusätzlichen Bindemitteln (DE-OS 38 14 996);
  • Inhomogene Bindemittelverteilung innerhalb der Matte, ebenfalls mit Anreicherung von Bindemitteln in der Mattenoberfläche (DE-P 32 33 385);
  • Übertragung der Umformkräfte vom Werkzeug auf die Mattenzuschnitte mit Hilfe von Gewebe-Schichten zur besseren Verteilung, vor allem aber zur Homogenisierung der Krafteinleitung (DE-P 27 59 279, DE-P 27 01 480);
  • Einlagerung von Geweben größerer Zugfestigkeit in die Mittelschicht der Fasermatten (DE-P 34 03 670, EP-OS 0 179 301);
  • Homogenes Einarbeiten von zugfesten Kunst- oder Naturfasern in die Holzfasermatte mit anschließendem Vernadeln der Matte, um deren Faserzusammenhalt zu erhöhen.
  • Einbringen von Kunst- oder Naturfasern höherer Festigkeit alternierend schichtweise in das gesamte Mattenvolumen (DE-P 39 17 787), und
  • Aufbringen von mit der Matte verbundenen Stabilisierungsauflagen, die im wesentlichen dehnungsfrei während der Verformung Zugkräfte aufnehmen können. Derartige Schichten werden in Form von Deckschichtauflagen aus Fäden höherer Zugfestigkeit vorgeschlagen, deren Dicke vernachlässigbar ist gegenüber der Dicke der Fasermatte (DE-P 37 21 663).
In detail, the technological development can be classified according to the state of interest here using the following keywords:
  • Enrichment of the mat surfaces with additional binders (DE-OS 38 14 996);
  • Inhomogeneous binder distribution within the mat, also with enrichment of binders in the mat surface (DE-P 32 33 385);
  • Transfer of the forming forces from the tool to the mat blanks with the help of fabric layers for better distribution, but above all for homogenizing the application of force (DE-P 27 59 279, DE-P 27 01 480);
  • Incorporation of fabrics with greater tensile strength in the middle layer of the fiber mats (DE-P 34 03 670, EP-OS 0 179 301);
  • Homogeneous incorporation of tensile synthetic or natural fibers into the wood fiber mat with subsequent needling of the mat to increase its fiber cohesion.
  • Introducing synthetic or natural fibers of higher strength alternating layers in the entire mat volume (DE-P 39 17 787), and
  • Applying stabilization pads connected to the mat, which can absorb tensile forces essentially without stretching during the deformation. Such layers are proposed in the form of cover layers made of threads of higher tensile strength, the thickness of which is negligible compared to the thickness of the fiber mat (DE-P 37 21 663).

Wenn auch - vor allem durch Kombination mehrerer der aufgeführten Maßnahmen - in letzter Zeit erheblicher technologischer Fortschritt auf dem Gebiet der Formteilfertigung aus Holzfasermatten erzielt werden konnte, so haften den einzelnen Maßnahmen jedoch auch heute noch nicht hinznehmende Mängel an. Bindemittelkonzentrationen in der Oberfläche, sei es nun als zusätzliche Beleimung oder als inhomogene Bindemittelverteilung, beeinflussen zwar die physikalischen Kennwerte des fertigen Formteiles, haben jedoch keinen Einfluß auf die Verformbarkeit der Fasermatten. Verformungshilfen in Form von Kraftübertragungstüchern zwischen Werkzeug und Fasermatte (Stabilisierungstücher), wie sie bis heute zur Fertigungstechnik gehören, wenn komplizierte Formgebungen erzielt werden müssen, sind aufwendig, teuer und verschleißen schnell. Auch die Einarbeitung von Geweben in die Mattenmitte führt nur zu unvollständigen Problemlösungen. Da die Umformkräfte über die Mattenoberflächen eingeleitet werden, ist die Wirkung von Verformungshilfen in der Mitte der Fasermatte nur unvollständig, so daß Beschädigungen bei komplizierterer Formgebung nur durch die zusätzliche Verwendung von Stabilisierungstüchern vermieden werden können. Die homogene Verteilung von zugfesten Zusatzfasern innerhalb einer Holzfasermatte und deren Verbindung mit der Holzfaser durch das Nadeln mittels Fäden führt zwar zu einer guten Verteilung der eingeleiteten Zugkräfte, die Vernadelung vermindert aber die Verschieblichkeit der Einzelfaser so sehr, daß komplizierte Formgebungen stark behindert werden. Darüber hinaus lassen sich bei derartigen Matten die Oberflächeneigenschaften - und damit alle oberflächenabhängigen Formteileigenschaften - nicht beeinflussen. Als Eigenschaft sei hier nur stellvertretend genannt, die Formteil-Festigkeit und -Steifigkeit infolge verbesserter mechanischer Eigenschaften der Außenschichten, der sogenannten Sandwich-Effekt, die Oberflächendichte, die Wasseraufnahme sowie die Haftgrundeigenschaften bei der Verklebung von Kaschierungen.Although considerable technological progress in the field of molded part production from wood fiber mats has recently been achieved, especially by combining several of the measures listed, the individual measures still have non-accepting shortcomings. Binder concentrations in the surface, whether as additional gluing or as an inhomogeneous binder distribution, influence the physical characteristics of the finished molded part, but have no influence on the deformability of the fiber mats. Deformation aids in the form of power transmission cloths between the tool and the fiber mat (stabilizing cloths), as they are still part of manufacturing technology today, when complicated shapes have to be achieved, are complex, expensive and wear out quickly. The incorporation of fabrics in the middle of the mat only leads to incomplete solutions to the problem. Since the forming forces are introduced via the mat surfaces, the effect of deformation aids in the middle of the fiber mat is only incomplete, so that damage is more complicated Shaping can only be avoided by the additional use of stabilizing wipes. The homogeneous distribution of tensile additional fibers within a wood fiber mat and their connection with the wood fiber by needling by means of threads leads to a good distribution of the tensile forces introduced, but the needling reduces the displaceability of the individual fibers so much that complicated shapes are severely hampered. In addition, the surface properties - and thus all surface-dependent molded part properties - cannot be influenced in such mats. As a characteristic, the strength and stiffness of the molded part due to the improved mechanical properties of the outer layers, the so-called sandwich effect, the surface density, the water absorption and the adhesive properties when gluing laminations are mentioned here as representative.

Das Einarbeiten der verschiedenen Verstärkungsfasern in alternierende Schichten verbindet zwar die Vorteile einer homogenen Faserverteilung mit guter Faserverschieblichkeit, eine Beeinflussung der Oberflächenqualität der späteren Formteile ist jedoch auch mit diesem Verfahren nicht möglich.The incorporation of the different reinforcing fibers in alternating layers combines the advantages of a homogeneous fiber distribution with good fiber displaceability, but it is also not possible with this method to influence the surface quality of the later molded parts.

Zusammenfassend läßt sich die vorliegende Problematik etwa wie folgt charakterisieren: Werden komplizierte Formteile gewünscht, so ist in der Fertigungspraxis immer noch das Dämpfen der Holzfasermatten, die Mehrstufenverformung und die Verwendung von Stabilisierungstüchern notwendig - insgesamt ein Aufwand, der die Produktion erschwert und verteuert.In summary, the present problem can be characterized as follows: If complicated molded parts are desired, steaming of the wood fiber mats, multi-stage deformation and the use of stabilizing cloths are still necessary in production practice - all in all, an effort that makes production more difficult and more expensive.

Der Erfindung liegt daher die Aufgabe zugrunde, Holzfasermatten der beschriebenen Art zu schaffen, deren Umformverhalten ohne zusätzlichen Materialaufwand verbessert ist.The invention is therefore based on the object to provide wood fiber mats of the type described, the shaping behavior of which is improved without additional material expenditure.

Diese Aufgabe wird durch die im kennzeichnenden Teil des Anspruches 1 angegebenen Merkmale gelöst. Die Unteransprüche geben vorteilhafte Weiterbildungen der Erfindung an.This object is achieved by the features specified in the characterizing part of claim 1. The subclaims indicate advantageous developments of the invention.

Dadurch, daß die die Oberflächen vorgebenden Außenschichten gegenüber der bzw. den überwiegend aus dem gleichen Material bestehenden Innenschichten eine höhere Verdichtung aufweisen, erhöht sich zunächst deren Zugfestigkeit, und zwar ohne zusätzlichen Materialaufwand. Sie können also mehr Zugkräfte übertragen und wirken wie die zusätzlichen Stabilisierungsschichten des angegebenen Standes der Technik.The fact that the outer layers defining the surfaces have a higher compression than the inner layers, which consist predominantly of the same material, initially increases their tensile strength, without additional material expenditure. They can therefore transmit more tensile forces and act like the additional stabilizing layers of the stated prior art.

Besonders vorteilhaft ist es dabei, daß alle zum erprobten Stand der Technik gehörenden Varianten der Holzfasermatten mit erfindungsgemäßer Zusatzverdichtung der Außenschichten versehen werden können; durch die Erfindung wird die Anwendungsbreite dieser Matten nicht eingeschränkt.It is particularly advantageous here that all variants of the wood fiber mats belonging to the tried and tested state of the art can be provided with additional compression of the outer layers according to the invention; the scope of application of these mats is not restricted by the invention.

Ein weiterer Vorteil erfindungsgemäßer Matten liegt darin, daß bei einer Zusatzverdichtung von mehr als 40 % der Außenschichten, die mindestens 20 Gew.% Fasermaterial der Matte enthalten, die Gesamtdicke der Matte gemindert wird. Fasermatten der beschriebenen Art werden bei der Formteilefertigung nicht nur geformt, sondern auch verdichtet. Hierbei treten an Stellen, an denen die Formteilflächen der Werkzeuge näherungsweise parallel zur Preßrichtung orientiert sind, Scherkräfte in der Fasermatte auf, die zu Reißern und Fehlstellen im Formteil führen. Die Dickenverminderung erfindungsgemäßer Holzfasermatten schafft also auch bessere Verformungsbedingungen. Dabei bleibt in dem Mittelbereich der Matte die für die Verformungsfähigkeit der Fasermatte notwendige Faserverschieblichkeit infolge der hier gegebenen geringeren Mattenverdichtung erhalten. Die höhere Zugfestigkeit der höher verdichteten Außenschichten und die daraus resultierende verbesserte Verformungsfähigkeit der Holzfasermatten, die nach wie vor erhaltene gute Verschieblichkeit der Fasern im größeren Teil der Matte und die verbesserten Verformungsbedingungen infolge der durch die verringerte Mattendicke verbesserten geometrischen Verhältnisse wirken dabei derart zusammen, daß beim Ausformen der Mattenzuschnitte zu Formteilen auf das Dämpfen der Fasermattenzuschnitte und auf zusätzliche zugkraftübertragende Hilfsmittel - wie Gewebeauflagen - in der Mehrzahl der Fälle verzichtet werden kann.Another advantage of mats according to the invention is that with an additional compression of more than 40% of the outer layers which contain at least 20% by weight of fiber material of the mat, the overall thickness of the mat is reduced. Fiber mats of the type described are not only shaped in the manufacture of molded parts, but also compressed. Here occur at places where the molding surfaces of the tools are oriented approximately parallel to the pressing direction are shear forces in the fiber mat, which lead to tears and defects in the molded part. The reduction in thickness of wood fiber mats according to the invention also creates better deformation conditions. In the central region of the mat, the fiber displaceability required for the deformability of the fiber mat is retained due to the lower mat compression given here. The higher tensile strength of the higher density outer layers and the resulting improved deformability of the wood fiber mats, the still good mobility of the fibers in the larger part of the mat and the improved deformation conditions due to the improved geometrical conditions due to the reduced mat thickness work together in such a way that at Forming the mat blanks into shaped parts, the damping of the fiber mat blanks and additional traction-transmitting aids - such as fabric coverings - can be dispensed with in the majority of cases.

Holzfasermatten der beschriebenen Art werden im Prinzip durch das Ausstreuen der beleimten Holzfasern auf ein laufendes Band erzeugt. Die Fasern erhalten dabei eine Vorzugsrichtung ihrer Orientierung in Laufrichtung des Bandes. Die Zugfestigkeit der die höhere Verdichtung aufweisenden Außenschichten ist infolgedessen anisotrop: quer zur Bildungsrichtung der Matten ist sie deutlich niedriger als in Bildungsrichtung. Die ist für die Ausformung der Matten zum Formteil nachteilig, da die Zugkräfte in jeder Oberflächenrichtung der Matte wirken können und übertragen werden müssen. Besteht die höherverdichtete Außenschicht aus einer Vielzahl von Einzellagen, deren Faseranordnungen zueinander annähernd orthotrop orientiert sind, sich also näherungsweise unter einem Winkel von 90° kreuzen, so wird dieser Nachteil vermieden, und die Fasermatte wird in ihren Verformungseigenschaften unabhängig von Verformungsrichtungen, also von der (späteren) Formteilgeometrie. Die Vielzahl von Einzellagen, aus denen die höher verdichteten Außenschichten mit orthotrop-orientierten Fasern gebildet wird, erleichtert dabei bei der Fertigung der Matten eine vollständige Orientierung der Fasern im gesamten Volumen der Außenschichten, da jeweils nur dünne Einzellagen "durchorientiert" werden müssen.Wood fiber mats of the type described are in principle produced by spreading the glued wood fibers onto a running belt. The fibers are given a preferred direction of orientation in the running direction of the belt. The tensile strength of the outer layers with the higher compression is consequently anisotropic: across the direction of formation of the mats, it is significantly lower than in the direction of formation. This is disadvantageous for the formation of the mats into the molded part, since the tensile forces can act in any surface direction of the mat and must be transmitted. The higher-density outer layer consists of a large number of individual layers, the fiber arrangements of which are approximately orthotropic to one another are oriented, that is to say they intersect approximately at an angle of 90 °, this disadvantage is avoided and the deformation properties of the fiber mat are independent of the directions of deformation, that is to say of the (later) molded part geometry. The large number of individual layers from which the higher-density outer layers are formed with orthotropically oriented fibers makes it easier for the mats to be completely oriented in the entire volume of the outer layers, since only thin individual layers have to be "completely oriented".

Eine Faserorientierung, bei der die orthotrope Ausrichtung der Fasern in den einzelnen Schichten alternierend wechselt, kann daher für die Mattenfertigung vorteilhaft sein.A fiber orientation in which the orthotropic orientation of the fibers changes alternately in the individual layers can therefore be advantageous for mat production.

Häufig werden Holzfasermatten in geringem Maße andere Fasermaterialien, z.B. Polymerfasern, zugemischt. Eine Zumischung von weniger als 45 % längerer Nicht-Holzfasern, bezogen auf das Gewicht der Außenschichten, bewirkt eine deutliche Erhöhung ihrer Zugfestigkeit und bewirkt eine deutliche Verbesserung der Verformungsfähigkeit der Matten. Der Begriff "längere Faser" bezieht sich dabei auf die Länge der kürzeren Holzfasern, die 10 mm nicht übersteigt.Wood fiber mats are often used to a small extent other fiber materials, e.g. Polymer fibers, mixed. The addition of less than 45% longer non-wood fibers, based on the weight of the outer layers, brings about a significant increase in their tensile strength and brings about a significant improvement in the deformability of the mats. The term "longer fiber" refers to the length of the shorter wood fibers, which does not exceed 10 mm.

Es wurde erfindungsgemäß gefunden, daß Matten, deren Außenschichten ein spezifisches Gewicht von mehr als 0,5 g/cm³ aufweisen, während das spezifische Gewicht der Mittellage zwischen 0,3 und 0,4 g/cm³ beträgt, ein optimales Eigenschaftsspektrum bezüglich Herstellung und Handhabung der Matten sowie der Formteilfertigung ergaben. Auch die Handhabung der Matten bei ihrer Lagerung, für den Zuschnitt und Transport wird durch höher verdichtete Außenschichten infolge der vergrößerten Plattensteifigkeit erleichtert.It has been found according to the invention that mats, the outer layers of which have a specific weight of more than 0.5 g / cm 3, while the specific weight of the middle layer is between 0.3 and 0.4 g / cm 3, have an optimal range of properties with regard to manufacture and handling the mats as well as the molding production. Also the handling of the mats Their storage, for cutting and transportation is facilitated by higher density outer layers due to the increased plate rigidity.

Die Erfindung wird nachstehend anhand der Figuren 1 und 2 näher erläutert und beispieslweise beschrieben.The invention is explained in more detail below with reference to FIGS. 1 and 2 and described in an exemplary manner.

Es zeigen:

Fig. 1
eine in schematische Schnittdarstellung den Unterschied zwischen homogen verdichteten Holzfasermatten nach dem Stand der Technik und erfindungsgemäßen Matten mit verdichteten Außenschichten.
Fig. 2
eine Möglichkeit zur Fertigung erfindungsgemäßer Matten
Zwischen der gestrichelt dargestellten Linienführung 9, 9' ist in Fig. 1 die geringer verdichtete Mittelschicht 1 einer dreischichtigen Fasermatte gezeigt. Ihre Dichte entspricht der üblichen Dichte der zum Stand der Technik gehörenden Rohmatten, sie liegt etwa zwischen 0,3 und 0,4 g/cm³. Die beiden gepunktet dargestellten zusätzlichen äußeren Verdichtungszonen 2 der erfindungsgemäßen Matte sind, wie ersichtlich, um eine bestimmte vorgenannte Dichte erhöht, bzw. ursprünglicher Dicke verringerte, was die Geamtdicke der Matte gleichzeitig herabsetzt und eine im wesentlichen materialidentische, höher zugfeste Außenschicht vorgibt.Show it:
Fig. 1
a schematic sectional view of the difference between homogeneously compressed wood fiber mats according to the prior art and mats according to the invention with compressed outer layers.
Fig. 2
a possibility for manufacturing mats according to the invention
Between the lines 9, 9 'shown in dashed lines in FIG. 1, the less compressed middle layer 1 of a three-layer fiber mat is shown. Their density corresponds to the usual density of the raw mats belonging to the state of the art, it lies approximately between 0.3 and 0.4 g / cm³. The two additional outer compression zones 2 of the mat according to the invention, shown in dotted lines, are, as can be seen, increased by a certain aforementioned density or reduced in their original thickness, which simultaneously reduces the overall thickness of the mat and provides an essentially material-identical, higher tensile outer layer.

In Fig. 2 sind verschiedene Streuvorrichtungen 6 für die Bildung der Außenschichten angedeutet, wobei die unverdickte Mittelschicht durch einen weiteren Streukopf 7, ausgestreut wird. Die umlaufenden Bänder 5, auf die das untereinander vorzugsweise identische und vorbeleimte Fasermaterial gestreut wird, laufen in Pfeilrichtung um und bewirken den Mattentransport. Zwei Kalanderwalzenpaare 3 sind vorgeheizt und bewirken sowohl die Verdichtung der beiden Außenschichten 2 als auch, fall erforderlich, deren verfestigende Stabilisierung durch Erweichen zumindest einer Komponente der Bindemittel ohne Vernetzung.In Fig. 2 different scattering devices 6 are indicated for the formation of the outer layers, the the thickened middle layer is spread by a further spreading head 7. The circumferential belts 5, onto which the preferably identical and pre-glued fiber material is scattered, run in the direction of the arrow and effect the mat transport. Two pairs of calender rolls 3 are preheated and cause both the compression of the two outer layers 2 and, if necessary, their stabilizing stabilization by softening at least one component of the binder without crosslinking.

Nachdem die die Gesamtmatte 8 bildenden Material-Teilströme 1 und 2 vor einem Endkalander 4 zusammengeführt sind, läßt sich hier ein Verdichtungsgrad der Mittelschicht 1 eingestellt. Die bereits höher vorverdichteten Außenschichten 2 werden in ihrer Verdichtung nicht mehr beeinflußt. jedoch durch den Druck der Kalanderwalzen 4 ausreichend fest mit der Mittelschicht 1 verbunden.After the partial material streams 1 and 2 forming the total mat 8 are brought together in front of an end calender 4, a degree of compaction of the middle layer 1 can be set here. The densification of the outer layers 2, which have already been pre-compressed, is no longer influenced. however, sufficiently firmly connected to the middle layer 1 by the pressure of the calender rolls 4.

Eine Faserorientierung in den vorverdichteten Außenschichten 2 der Fasermatte 1, 2 kann beispielsweise dadurch erreicht werden, daß die Kalanderwalzen 3 Oberflächenmuster, beispielsweise in Form von Schrägrillungen, aufweisen.A fiber orientation in the pre-compressed outer layers 2 of the fiber mat 1, 2 can be achieved, for example, in that the calender rolls 3 have surface patterns, for example in the form of oblique grooves.

Die Fig. 2 zeigt beispielsweise, wie erfindungsgemäße Dreischichtmatten 8 gefertigt werden können. Andere Vorgehensweisen, auch eine größere Schichtzahl sind möglich; z.B. können materialidentische Außenschichten 2 auch separat vorgefertigt werden und auf andere Weise mit der Mittelschicht 1 verbunden werden.2 shows, for example, how three-layer mats 8 according to the invention can be produced. Other procedures, even a larger number of layers are possible; e.g. outer layers 2 identical to the material can also be prefabricated separately and connected to the middle layer 1 in another way.

Claims (5)

  1. Lignocellulose or wood-fibre multi-layer matting containing bonding agents for producing spatially deformable shapes for interior panelling of vehicles, characterized in that the outer layers representing the surfaces are of higher density than the inner layer(s) which is/are predominantly made of the same material, and that the weight proportion of the outer layers is at least 20% of the weight of the entire matting, and the density of the outer layers is at least 40% higher.
  2. A multi-layer matting according to claim 1, characterized in that each of the outer layers is composed of a plurality of individual layers the fibre arrangements of which are virtually orthotropic to each other.
  3. A multi-layer matting according to claim 1 and 2, characterized in that the orthotropic orientation of the fibres changes alternatingly in the individual layers.
  4. A multi-layer matting according to claim 1 to 3, characterized in that the outer layers contain a proportion of longer non-wood fibres, relative to the weight of the outer layers, of less than 45%.
  5. A multi-layer matting according to at least one of the above claims, characterized in that the outer layers have a specific weight of more than 0.5 g/cm³, and the density of the middle layer is between 0.3 and 0.4 g/cm³.
EP93108937A 1992-06-04 1993-06-03 Fibre mats containing a binding agent made from cellulosic and ligno-cellulosic fibres Expired - Lifetime EP0573039B1 (en)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
DE4218444 1992-06-04
DE4218444A DE4218444A1 (en) 1992-06-04 1992-06-04 Binder-containing fiber mats made from cellulose or lignocellulose fibers

Publications (2)

Publication Number Publication Date
EP0573039A1 EP0573039A1 (en) 1993-12-08
EP0573039B1 true EP0573039B1 (en) 1995-08-30

Family

ID=6460394

Family Applications (1)

Application Number Title Priority Date Filing Date
EP93108937A Expired - Lifetime EP0573039B1 (en) 1992-06-04 1993-06-03 Fibre mats containing a binding agent made from cellulosic and ligno-cellulosic fibres

Country Status (5)

Country Link
EP (1) EP0573039B1 (en)
JP (1) JPH06235153A (en)
CA (1) CA2097663A1 (en)
DE (2) DE4218444A1 (en)
ES (1) ES2078087T3 (en)

Families Citing this family (13)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE4342789C2 (en) * 1993-12-15 1996-03-07 Lignotock Gmbh Process for the production of molded parts
DE4434876B4 (en) * 1994-09-29 2004-09-16 Dieffenbacher Gmbh + Co. Kg Process and plant for the continuous production of a multilayer board
DE4438764A1 (en) * 1994-10-29 1996-05-02 Hp Chemie Pelzer Res & Dev Cheap, lightweight, noise-absorbing laminate for use in automobiles
DE19535559C1 (en) * 1995-09-12 1997-05-15 Lignotock Gmbh Hot pressed wood mats contg. binder, useful for making e.g. vehicle panels
DE19606262C1 (en) * 1996-02-21 1997-04-17 Glunz Ag Medium density fibreboard rapid prodn. achieved by steam shock heating
US6197414B1 (en) 1997-12-25 2001-03-06 Matsushita Electric Works, Ltd. Fiberboard and manufacturing method thereof
DE10320686B4 (en) * 2003-04-30 2015-02-05 Faurecia Innenraum Systeme Gmbh Process for the production of molded body base material
DE102004062649C5 (en) 2004-12-21 2013-06-06 Kronotec Ag Process for the production of a wood fiber insulation board or mats and wood fiber insulation boards or mats produced by this process
DE102005038734A1 (en) 2005-08-16 2007-02-22 Michanickl, Andreas, Prof.Dr. Multilayer wood material plate for e.g. furniture, has middle layer made of very light, porous and pressure resistant chipboard and cover layers made of very thin and firm fiberboard or laminar material with well closed surface
DE102005057606A1 (en) * 2005-12-02 2007-06-06 Günther Isensee Modellbaubedarf Process for producing a balsa wood chipboard
DE102009056581A1 (en) 2008-11-25 2010-06-10 Technische Universität Dresden Blank with good storage properties, used for molding e.g. vehicle linings and claddings, is made by hot-pressing mixture of lingo-cellulose- and thermoplastic fibers
EP2695711A1 (en) * 2012-08-09 2014-02-12 Dascanova GmbH Method and apparatus for the production of a particle based element with precompression of a portion of the particles
CN111391042A (en) * 2020-04-21 2020-07-10 南宁科天水性科技有限责任公司 Double-line type equipment for manufacturing artificial board with wood shaving decorative surface

Family Cites Families (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE1100927B (en) * 1958-03-04 1961-03-02 Ind Companie Kleinewefers Kons Method and device for aligning the chips of a chipboard for the production of chipboard
CH368612A (en) * 1959-09-09 1963-04-15 Abitibi Power & Paper Co Apparatus for forming an anisotropic layer of wood particles of various sizes
FR2281214A1 (en) * 1974-08-05 1976-03-05 Azote & Prod Chim Particle board with integral film covers - prepd by continuous adhesive consolidation between heated rolls
DE7535229U (en) * 1975-11-06 1976-03-18 G. Siempelkamp & Co, 4150 Krefeld CHIPBOARD, FIBERBOARD OR THE SAME
US4283450A (en) * 1976-11-05 1981-08-11 Masonite Corporation Product containing high density skins
DE3233385C2 (en) * 1981-10-02 1984-05-17 Günter Hans 1000 Berlin Kiss Multi-layer fiber composite and process for its manufacture
JPS5876561A (en) * 1981-10-02 1983-05-09 ギユンタ−・ハ−・キス Multilayer fiber mat and production thereof
SE458839B (en) * 1988-03-16 1989-05-16 Inst Traeteknisk Forskning PROCEDURES FOR THE PREPARATION OF CHEESE DISCOVERED MACHINES DETAILED ACCORDING TO THE PROCEDURE

Also Published As

Publication number Publication date
DE4218444A1 (en) 1993-12-09
EP0573039A1 (en) 1993-12-08
DE59300524D1 (en) 1995-10-05
ES2078087T3 (en) 1995-12-01
JPH06235153A (en) 1994-08-23
CA2097663A1 (en) 1993-12-05

Similar Documents

Publication Publication Date Title
EP0106249B1 (en) Plastic material leafsprings and method for their manufacture
DE102006018277B4 (en) Building board and method for producing a building board
DE69233415T2 (en) METHOD AND DEVICE FOR PRODUCING ROSES FROM FIBERS
EP0573039B1 (en) Fibre mats containing a binding agent made from cellulosic and ligno-cellulosic fibres
DE3486310T2 (en) Process for assembled wood products.
DE1299115B (en) Extruded chipboard
EP1721715B1 (en) Chip board panel, method and apparatus of manufacturing the panel
EP4010158B1 (en) Material board and method for producing a material board
DE3343330C2 (en)
DE69423612T2 (en) METHOD FOR PRODUCING A MINERAL FIBER TRAIN, AND A PLANT FOR PRODUCING A MINERAL FIBER TRAIN
EP1469140B1 (en) Process for production of a panel with a core of a wood-based material
EP0927790A2 (en) Process for making laminated boards, pencilboards and/or stems for writing-, drawing- or painting instruments
DE60304032T2 (en) FURNITURE CHIPBOARD
DE10049050A1 (en) Oriented strand board with a shavings core and long chip outer layers, are obtained inexpensively with high bending modulus by using specified particle geometrical composition, core shavings content and pressure profile
DE20015725U1 (en) Wood particle board, especially formwork board
EP3421200B1 (en) Composite wood board with hollow balls
DE4212732A1 (en) Fibrous moulding prodn. reinforced with e.g. metallic layer - by pressing two fibre mats with separator between, delaminating at separator, placing reinforcement on one mat and pressing second mat on top
EP2078599B1 (en) Chipboard
EP1792698A2 (en) Reinforced board
DE19535559C1 (en) Hot pressed wood mats contg. binder, useful for making e.g. vehicle panels
EP0548758A1 (en) Board and method to manufacture it
DE102018115121A1 (en) Manufacturing process for resin composite panels
EP2786849B1 (en) Method for producing a multi-layered fibreboard panel, and a multi-layered fibreboard panel
DE102007054711B4 (en) Method for producing a thin chipboard with increased stability and thin chipboard with increased stability
EP2062709B1 (en) Boards made from wood fibres using a bonding agent

Legal Events

Date Code Title Description
PUAI Public reference made under article 153(3) epc to a published international application that has entered the european phase

Free format text: ORIGINAL CODE: 0009012

AK Designated contracting states

Kind code of ref document: A1

Designated state(s): AT BE CH DE DK ES FR GB GR IE IT LI LU MC NL PT SE

17P Request for examination filed

Effective date: 19931124

RBV Designated contracting states (corrected)

Designated state(s): DE ES FR GB IT

17Q First examination report despatched

Effective date: 19941111

GRAA (expected) grant

Free format text: ORIGINAL CODE: 0009210

AK Designated contracting states

Kind code of ref document: B1

Designated state(s): DE ES FR GB IT

GBT Gb: translation of ep patent filed (gb section 77(6)(a)/1977)

Effective date: 19950829

REF Corresponds to:

Ref document number: 59300524

Country of ref document: DE

Date of ref document: 19951005

ITF It: translation for a ep patent filed
REG Reference to a national code

Ref country code: ES

Ref legal event code: FG2A

Ref document number: 2078087

Country of ref document: ES

Kind code of ref document: T3

ET Fr: translation filed
PLBE No opposition filed within time limit

Free format text: ORIGINAL CODE: 0009261

STAA Information on the status of an ep patent application or granted ep patent

Free format text: STATUS: NO OPPOSITION FILED WITHIN TIME LIMIT

26N No opposition filed
REG Reference to a national code

Ref country code: GB

Ref legal event code: IF02

PGFP Annual fee paid to national office [announced via postgrant information from national office to epo]

Ref country code: FR

Payment date: 20050627

Year of fee payment: 13

PGFP Annual fee paid to national office [announced via postgrant information from national office to epo]

Ref country code: GB

Payment date: 20050704

Year of fee payment: 13

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: GB

Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES

Effective date: 20060603

PGFP Annual fee paid to national office [announced via postgrant information from national office to epo]

Ref country code: IT

Payment date: 20060630

Year of fee payment: 14

PGFP Annual fee paid to national office [announced via postgrant information from national office to epo]

Ref country code: DE

Payment date: 20060821

Year of fee payment: 14

GBPC Gb: european patent ceased through non-payment of renewal fee

Effective date: 20060603

REG Reference to a national code

Ref country code: FR

Ref legal event code: ST

Effective date: 20070228

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: FR

Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES

Effective date: 20060630

Ref country code: DE

Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES

Effective date: 20080101

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: IT

Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES

Effective date: 20070603

PGFP Annual fee paid to national office [announced via postgrant information from national office to epo]

Ref country code: ES

Payment date: 20100616

Year of fee payment: 18

REG Reference to a national code

Ref country code: ES

Ref legal event code: FD2A

Effective date: 20120717

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: ES

Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES

Effective date: 20110604